Henry111's free tech support thread

[dogman dan]

If aluminum, then you need the steel of the TA,, both sides if possible.

If nothing fits well, make your own with a grinder, drill, and small file.

 

[MrDude_1]

The short answer is... its always a good idea.
can you do it without one? sure... with low power and no regen in steel, it should last longer than the batteries.
but...
if your nuts are not tight... ever... it will spread.

if you are doing regen, you need it. if you do any higher power stuff, you need it. if its aluminum, you need it...

regen rocks the bar back and forth. this wears and spreads the thin contact points in the dropout.
higher power is trying to hold alot of torque on the small points it touches... it will spread.
if its aluminum, it will spread. too much load on where the corner points are.


I have to ask though, whats your aversion to having a torque arm anyway?its only one small bolt when you remove the wheel.

 

[Henry111]

Do most ready-to-ride production bikes, like Pedego, or Prodego, or Izip come with torque arms?

 

[keithmac]

My Gteck comes with bespoke frame for the Carbon Belt, the have made the dropout and motor brakets so no torque arm is necessary (very well thought out!).

 

[dogman dan]

The specific answer will require a picture of your frame.

Even a steel bike needs torque arms if the dropouts are vertical and shallow. the semi horizontal steel frame dropout may not need a TA.

 

[Drunkskunk]

"Never ride without protection, or you'll end up spreading things you never meant to spread."

My Grandpappy taught me that when I was 12. I'm pretty sure he was talking about torque arms and drop outs.


Unless you have a frame built specifically for holding a motor, use a torque arm every time. Without them, One lose nut, one time, and you have a destroyed frame, a damaged or destroyed motor, and a chance for a serious to even fatal crash.

 

[flat tire]

I run like 3KW thru my motor and don't use torque arms. My bikes have really strong aluminum dropouts tho and also I torque my nuts properly. On my old bike the nuts came untorqued but the motor didn't spin in the Al dropouts because they're super thick. With a 750W motor and 36V battery, I wouldn't think you would need any kind of dropouts unless your bike is a piece of crap (probably pretty likely if you're putting up with a 750w hub motor and 36v batteries).

Of course I want foolproof so I'm gonna weld up a steel swingarm with really strong dropouts.

 

[dogman dan]

Yes, if your nuts stay tight, the nut pressure can hold back a lot of torque. It's for when a nut somehow gets loose that you need the TA, or at least, a very strong dropout.

 

[999zip999]

Yes you need torque arms. Yes needed.

 

[MrDude_1]

There is an old saying that applies - There are OLD e-bike riders, and there are BOLD e-bike riders, but there are no Old, Bold e-bike riders.

Damn good thing that doesnt apply to motorcycles, or I would be dead right now. :lol:

 

[wesnewell]

There is an old saying that applies - There are OLD e-bike riders, and there are BOLD e-bike riders, but there are no Old, Bold e-bike riders.

I turn 70 this month and have had my ebike airborne over 60 mph. Nice to know I'm not OLD.

 

[flat tire]

There is an old saying that applies - There are OLD e-bike riders, and there are BOLD e-bike riders, but there are no Old, Bold e-bike riders.

I turn 70 this month and have had my ebike airborne over 60 mph. Nice to know I'm not OLD.

Bold is riding outside your skill set and your equipment's envelope. If your skills and equipment allow 60 MPH jumps then you're not being bold so much as enjoying riding within the means of your advanced skillset. I know a bunch of MX riders who could do that stuff in their sleep, the question is more if your bike is structurally beefy enough to handle it.

 

[999zip999]

Wesnewell need to see pic of your 60mph flyer.

 

[Henry111]

Do I have to use a 48V battery on a 1000W motor.
Can I use a 36V battery?
And if I do run this 1000W motor with a 36V battery, what would be the result in terms of watts, or power?

 

[flat tire]

Sure you can run it on 36v if your controller is up to the challenge. Depending again on the controller, it can make at least 1kw on 36v, probably more but of course you will be hot rodding it.

Most importantly, your top speed may be reduced over someone running 48v or more. I ran 19s 25r with one of these motors @ 79v max and it did 44 mph top speed. Other things equal, with more voltage you can put more power into the motor without overheating it since you'll be running reduced amperage for a given power level as input power = volts * amps.

 

[Henry111]

Here is a copy of the label on my speed controller.
Can someone please explain to me what each line means? What does it tell me?

 

[wesnewell]

1 rated for 48V nominal.
2 Low Voltage Cutoff is 42V.
3 Limited to 30A max current.
4 120 degree phase angle motors.

 

[Adverse Effects]

1 rated for 48V nominal.
2 Low Voltage Cutoff is 42V.
3 Limited to 30A max current.
4 120 degree phase angle motors.

hehehe i love being a smart ass at times

[TROLL MODE ON]
Dude you you have no idea what your talking about
(giggle)
ITS

2 Low Voltage Cutoff is somewhere around 41.5V to 42.5V.
3 Limited to somewhere around 29A to 31A max current.
4 and the motor can get really HOT 120 degree
5 cheep china crap that is never in spec anyway

[TROLL MODE OFF]

HAHAHAHAHAHAHA

 

[nutnspecial]

^ LOL

The label should kinda be self expanatory if you own such a device, imo, except maybe the 120deg phase, though that one is largely standard among 3 phase brushless motors anyway.

Further explanation? You run the controller @ ~ 48v. Capacitors (which are the limiting factor for voltage) are prob good till ~65v fully charged, so up to 15s lipo/18650 is acceptable, but the low cutoff setting is best utilized for 12s (@ 3.5 avg cell). Programable controllers are way nicer to use a low cutoff for battery, but all batteries with bms already have one anyway so just run a standard pack of 12- 15s.

And limited current means it will draw up to ~30a for whatever motor it is driving , so the battery should be able to produce 30a for at least a short period of time on wot.

 

[Henry111]

"Further explanation? You run the controller @ ~ 48v. Capacitors (which are the limiting factor for voltage) are prob good till ~65v fully charged,"

With the above statement are you saying that I could run with a 65 volt battery?
The motor is rated at 600W.

 

[999zip999]

a fully charged 15s battery is 63 volts. A fully charged lifepo4 16s is 59 volts. If you open your controller and read the caps. It may read 63v or 65v maybe 75v. This is the controlling factor. The controller can spike higher than 34 amp. Most 48volt batteried are 13s or 14s lipo , liMn ect. Lifepo4 is 3.3v normal ois3.6v fully charged. Lifepo4 is 15s or mainly 16s cell 3.2v and charged to 3.6v. These is way you buy a goog quality battery with quality cells and charger from the same place. Or just roll the dice on ebay if you fill lucky.
Do tell which motor you have. A link to both
Meaning lots of variables.
Sorry tapping these out on my phone.

 

[spinningmagnets]

The Low Voltage Cutoff (LVC) is when the battery is used up and the voltage is low enough that some component in the system need to turn the system off, because if the batteries are drawn down lower than the generally accepted level, they might become damaged. An LVC of 41.5V-42.5V means that...if you accept an LVC of 3.2V per cell, then 42V-LVC = 13S / 48V

The 120-degrees is the configuration of the hall sensors, with your options being 60-deg, or 120-deg. It has been specified here so you can use this controller with various motors.

 

[nutnspecial]

With the above statement are you saying that I could run with a 65 volt battery?
The motor is rated at 600W.

As zip says, it would be the best to confirm the cap ratings for certain, but yes I think it's likely you could run up to a 15s battery ('15s' is 15 cell groups in series x 4.2v each when fully charged = 63v). Get a normal pack with bms and you don't need to worry about the controller cutoff setting.

Alot of motors rated for 800 or 1000w can take 2kw or more. . . also as zip said, you should share what motor it is. Regardless, you could run any motor on any reasonable voltage, but you want to match up the system well. 15s x 3.7v nominal x ~30a would be a nice 1600w peak.

 

[999zip999]

Also weight, luggage and hills.

 

[Chalo]

Capacitors (which are the limiting factor for voltage) are prob good till ~65v fully charged,

With the above statement are you saying that I could run with a 65 volt battery?

No, that's not what he's saying. A nominally 48V battery charges to about 55V, which is roughly what the controller sees when you first start after a fresh charge.

The capacitors in a 48V controller are most likely rated 60V, and they might take a little more but are not certified to do so. 3077 FETs have a limit of about 73V, which would tolerate a working voltage of about 65V.

A nominally 52V battery charges to about 59V, so hypothetically you can use one of those with a 48V controller. But that doesn't leave much headroom for voltage fluctuations coming from the motor (which is a big inductor).

You can't use a 65V battery, whether nominal or fully charged voltage, without expecting to pop something in the controller, most probably a capacitor.